package com.apache.netty.buf;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;

import java.nio.charset.Charset;

public class NettyByteBuf02 {
  public static void main(String[] args) {

    // 创建ByteBuf
    ByteBuf byteBuf = Unpooled.copiedBuffer("hello,world!", Charset.forName("utf-8"));

    // 使用相关的方法
    if (byteBuf.hasArray()) { // true

      byte[] content = byteBuf.array();

      // 将 content 转成字符串
      System.out.println(new String(content, Charset.forName("utf-8")));

      System.out.println("byteBuf=" + byteBuf);

      System.out.println(byteBuf.arrayOffset()); // 0
      System.out.println(byteBuf.readerIndex()); // 0
      System.out.println(byteBuf.writerIndex()); // 12
      System.out.println(byteBuf.capacity()); // 36

      // System.out.println(byteBuf.readByte()); //
      System.out.println(byteBuf.getByte(0)); // 104

      int len = byteBuf.readableBytes(); // 可读的字节数  12
      System.out.println("len=" + len);

      // 使用for取出各个字节
      for (int i = 0; i < len; i++) {
        System.out.println((char) byteBuf.getByte(i));
      }

      // 按照某个范围读取
      System.out.println(byteBuf.getCharSequence(0, 4, Charset.forName("utf-8")));
      System.out.println(byteBuf.getCharSequence(4, 6, Charset.forName("utf-8")));
    }
  }
}
